I have found a beautifully ordered DTT molecule stretching across a crystallographic two-fold and linking two symmetry related cysteine side chains. Since part of this molecule sits on across the two-fold (special position) I will specify the occupancy as 0.5. I am hoping to get some information on how easy (or how difficult) it is to specify this arrangement in Phenix for refinement since it is covalent and sitting across a crystallographic two-fold (and presumably stabilizing the lattice). Will ReadySet build the appropriate CIF file if I build the DTT into the density and give it a 0.5 occupancy?

Joe